Rotating shaft

Abstract

The present invention provides a rotating shaft having a structure in which the attachment and detachment of a member such as a knob to and from the rotating shaft can be efficiently performed, and the member is not separated when a small force is applied, but is separated when a large force is applied, so that the rotating shaft is a rotating shaft in which the member is attached to the outside thereof. The rotating shaft has a root portion and a tip portion located closer to the tip side of the rotating shaft than the root portion, the root portion has a cylindrical shape, and a portion of the cylindrical shape of the tip portion is cut out in the axial direction to form a planar portion, so that the cross section of the tip portion is substantially D-shaped. A recessed portion is formed on the curved surface portion of the tip portion.

Description

Technical Field

[0001] This disclosure relates to a rotating shaft for mounting components such as variable resistors, switches, and adjustment knobs. Background Technology

[0002] As an example of a structure in which an operating knob is mounted on a rotating shaft used for adjusting the characteristics of variable resistors, switches, etc., there are structures described in Patent Documents 1 and 2. In these structures, by operating the knob to rotate the rotating shaft around the shaft, operations such as changing the resistance value and switching the switch can be performed.

[0003] Figure 10 An example of prior art is shown of a rotating shaft 31 with a knob 41 mounted on it. The rotating shaft 31 is generally cylindrical in shape, with a generally circular cross-section at the root 33 and a portion of the front end 35 cut off to form a flat portion 37, so that the cross-section of the front end 35 is generally D-shaped.

[0004] On the other hand, the knob 41 has an insertion hole 43 for inserting the rotating shaft 31. In addition, a fastening component 45, such as a screw, is provided on the knob 41 so that it can be inserted into the insertion hole 43.

[0005] Insert the rotating shaft 31 into the insertion hole 43, so that the knob 41 is fitted and mounted on the rotating shaft 31. At this time, align the fastening member 45 with the flat part 37 in the direction about the OO axis of the knob 41. Then, insert the fastening member 45 into the insertion hole 43 and abut against the flat part 37 to achieve fastening.

[0006] When operating the rotating shaft 31, the rotating shaft 31 also rotates when the knob 41 rotates around the OO axis, thereby enabling the adjustment of the resistance value and other characteristics of the variable resistor.

[0007] When removing the knob 41 from the rotating shaft 31 for maintenance or replacement, first loosen the fastening part 45, and then remove the knob 41.

[0008] Figure 11 This illustrates another existing technology. In this example, the structure of the rotating shaft 31 is similar to... Figure 10 The same as in the example. On the other hand, the shape of the insertion hole 53 of the knob 51 is the same as... Figure 10 The insertion hole 43 in the example shown is different. In this example, the portion of the insertion hole 53 opposite to the flat portion 37 extends into the insertion hole 53 as a protrusion 55, and the outer surface shape of the rotating shaft 31 is approximately the same as the inner surface shape of the insertion hole 53.

[0009] A D-spring 61 is inserted by pressing into the portion of the insertion hole 53 opposite to the front end 35. (Refer to...) Figure 12As can be seen, the D-spring 61 is a cylindrical component with a D-shaped cross-section, having a curved portion 63 and a flat portion 65, and is formed in such a way that its cross-sectional shape is approximately the same as the cross-sectional shape of the portion into which the D-spring 61 is inserted. Furthermore, a constricted portion 67 protruding inward is formed on a portion of the curved portion 63. If the rotating shaft 31 is inserted into the insertion hole 53 after the flat portion 37 of the rotating shaft 31 is aligned with the flat portion 65 of the D-spring 61 and the protruding portion 55 of the insertion hole 53, the constricted portion 67 elastically abuts against the outer surface of the front end portion 35 to achieve a fastening, thereby fixing the knob 51 to the rotating shaft 31.

[0010] and Figure 10 Compared to the examples, in Figure 11 In the example, when installing the knob 51 onto the rotating shaft 31, installation can be completed simply by inserting the rotating shaft 31 into the insertion hole 53. Furthermore, when the knob 51 needs to be removed for maintenance or other purposes, it can be removed simply by pulling out the knob 51, thus enabling efficient installation and removal operations.

[0011] Existing technical documents

[0012] Patent documents Patent Document 1: Microfilm of Japanese Patent Application No. 58-11339 (Patent Application No. 59-116722) Patent Document 2: Microfilm of Japanese Patent Application No. 53-67998 (Patent Application No. 54-169692) Summary of the Invention The problem the invention aims to solve exist Figure 11 In the prior art shown, the knob 51 and the rotating shaft 31 are fixed only by the frictional force generated between the inner surface of the D spring 61 and the outer surface of the rotating shaft 31 based on the elastic force of the D spring 61. Therefore, although the installation and disassembly operations are highly efficient, the knob 51 may be accidentally dislodged due to the action of a small force.

[0013] The purpose of this disclosure is to provide a rotating shaft that allows for efficient installation and removal of components such as knobs from the rotating shaft, and that does not detach under small forces but detaches under large forces.

[0014] Solution to the problem The rotating shaft disclosed herein is a rotating shaft on which a component is mounted. The rotating shaft has a root and a front end portion located on the front end side of the rotating shaft, which is closer to the root than the front end portion. The root is cylindrical, and a portion of the cylindrical part of the front end portion is cut off axially to form a planar portion, so that the cross-section of the front end portion is generally D-shaped, and a recess is formed on the curved portion of the front end portion.

[0015] Invention Effects According to this disclosure, when the component is mounted on the rotating shaft, a portion of the component engages with a recess formed on the curved surface portion of the front end. Therefore, the mounting and dismounting of the component onto the rotating shaft can be performed efficiently. Furthermore, the component is mounted in such a way that when a force is applied to the mounted component in the direction that causes the component to disengage from the rotating shaft, the component will not disengage under a smaller force, but will disengage under a larger force. Attached Figure Description

[0016] Figure 1 This is a diagram illustrating an example of the first embodiment; Figure 2 This is a diagram illustrating an example of the first embodiment; Figure 3 This is a diagram illustrating an example of the first embodiment; Figure 4 This is a diagram illustrating an example of the second embodiment; Figure 5 This is a diagram illustrating an example of the second embodiment; Figure 6 This is a diagram illustrating an example of the third embodiment; Figure 7 This is a diagram illustrating an example of the fourth embodiment; Figure 8 This is a diagram illustrating an example of the fifth embodiment; Figure 9 This is a diagram illustrating an example of the sixth embodiment; Figure 10 It is a diagram representing existing technology; Figure 11 It is a diagram representing existing technology; Figure 12 This is a diagram illustrating an example of spring D. Detailed Implementation

[0017] Hereinafter, examples of the rotation axis and other components of embodiments of the present disclosure will be described with reference to the accompanying drawings. Furthermore, all drawings are schematic diagrams and are not necessarily drawn to scale. Also, in each drawing, substantially identical structural elements are labeled with the same reference numerals, and sometimes repeated descriptions are omitted or simplified.

[0018] Figures 1 to 3 This is a schematic diagram illustrating the first embodiment of the present disclosure. Figure 1In this design, the root 3 of the rotating shaft 1 is formed into a roughly circular cylindrical shape in circumferential cross-section (AA cross-section). On the other hand, a portion of the circumferential direction of the front end portion 5 is cut off to form a flat portion 7, thereby forming the front end portion 5 into a roughly D-shaped cross-section (BB cross-section). In addition, a recess 9 is formed at a constant depth along the circumferential direction on the curved portion of the front end portion 5 (CC cross-section).

[0019] exist Figure 2 In the middle, the recess 9 is groove-shaped, and its cross-section along the axial direction is approximately rectangular. A front wall 13 is formed on the front end side of the bottom 11 at approximately a right angle to the bottom 11, and a rear wall 15 is formed on the root side of the bottom 11 at approximately a right angle to the bottom 11.

[0020] Figure 3 The diagram shows the rotating shaft 1 and spring 61 when the knob (not shown) is mounted on the rotating shaft 1. The structure of the knob and the spring 61 mounted in its insertion hole is similar to... Figure 11 The prior art shown is the same. With the knob mounted on the rotating shaft 1, the contraction portion 67 formed on the curved surface 63 of the D-spring 61 elastically engages with the recess 9. Thus, the front end 5 is pressed into the D-spring 61, secured by the flat portion 65 and the contraction portion 67, and positioned axially by the engagement of the recess 9 and the contraction portion 67. Therefore, even if a force is applied to the knob in the direction of disengaging it from the rotating shaft 1 when the knob is operated, disengagement is prevented by the contraction portion 67 engaging with the recess 9. On the other hand, when the knob needs to be removed from the rotating shaft 1 for maintenance, a larger force is applied to the knob, causing the contraction portion 67 to elastically deform and disengage from the recess 9, thereby allowing the knob to be removed from the rotating shaft 1.

[0021] Figure 4 and Figure 5 This is a schematic diagram illustrating the second embodiment of the present disclosure. In the first embodiment, the cross-sectional shape of the recess 9 is approximately rectangular. In contrast, in the second embodiment, the cross-sectional shape of the recess 9 is approximately arc-shaped, matching the shape of the contraction portion 67 of the D spring 61. The recess 9 is configured such that when the knob is mounted on the rotating shaft 1, the contraction portion 67 of the D spring 61 and the recess 9 are fitted together almost seamlessly and engage. As a result, looseness when the knob is mounted on the rotating shaft 1 is reduced, and the friction between the recess 9 and the contraction portion 67 plays a greater role, more effectively preventing the knob from disengaging.

[0022] Figure 6This is a schematic diagram illustrating a third embodiment of the present disclosure. In this example, the rear wall 15 of the recess 9 is formed at approximately a right angle to the bottom 11, while the front wall 13 is formed in a manner that slopes towards the rear wall 15 as it moves away from the bottom 11. As a result, when a force is applied to the knob in the direction that would disengage the knob, the front wall 13 engages with the contraction portion 67, thereby more effectively preventing the knob from disengaging.

[0023] Figure 7 This is a schematic diagram illustrating the fourth embodiment of the present disclosure. In this example, the shape of the front wall 13 of the recess 9 is the same as in the third embodiment, while the rear wall 15 is formed as a convex arc shape, and the rear wall 15 is smoothly connected to the outer peripheral surface of the rotating shaft 1. This effectively prevents the knob from disengaging and also effectively prevents wear near the connection between the rear wall 15 and the outer peripheral surface of the rotating shaft 1 when the knob is attached or detached from the rotating shaft 1.

[0024] Figure 8 This is a schematic diagram illustrating the fifth embodiment of the present disclosure. In this example, the rear wall 15 is formed into a concave arc shape so as to smoothly connect with the bottom 11 of the recess 9. This effectively prevents the knob from coming off and also increases the strength near the connection between the rear wall 15 and the bottom 11.

[0025] Figure 9 This is a schematic diagram illustrating the sixth embodiment of the present disclosure. In this example, the rear wall 15 is formed into an arc shape that can fit tightly against the contraction portion 67 of the D spring 61. On the other hand, the front wall 13 is formed in the same way as in the third embodiment, and its shape is that of the second embodiment ( Figure 4 , 5 ) and the third implementation method ( Figure 6 The shape is formed by combining the recesses in the front wall 15. As a result, due to the tight contact between the rear wall 15 and the contraction part 67, the friction between the rotating shaft 1 and the D spring 61 increases, thereby reducing the loosening of the knob. Furthermore, since the front wall 13 bites into the contraction part 67, the knob can be more effectively prevented from coming off.

[0026] In the above embodiments, the recess 9 is formed in a groove shape along the circumferential direction at the front end portion 5. However, as long as the contraction portion 67 can engage, multiple recesses can also be formed independently in the circumferential direction. Furthermore, the number of recesses can be different from the number of contraction portions 67. In addition, the shape of the recesses is not limited to the shape shown in the above embodiments. The shapes of the recesses illustrated in the above embodiments can be appropriately combined. In short, regardless of the number and shape of the recesses, any shape that can engage with the contraction portion 67 is included within the scope defined by the claims of the present invention.

[0027] The entire contents of the description, drawings and abstract contained in Japanese Patent Application No. 2023-165922, filed on September 27, 2023, are incorporated herein by reference.

[0028] Industrial applicability This invention can be effectively applied when mounting components onto a rotating shaft.

[0029] Explanation of reference numerals in the attached figures 1. Rotation axis; 3. Roots; 5. Front end; 7. Planar part; 9 recess; 11. Bottom; 13. Anterior wall; 15. Rear wall; 61 D spring; 63. Curved face; 65. Flat area; 67. Contraction section.

Claims

1. A rotating shaft, wherein a component is mounted on its outer side, characterized in that, The rotating shaft has a root and a front end located on the front end side of the rotating shaft, which is closer to the root. The root is cylindrical. In the front end portion, a portion of the cylindrical shape is cut off axially to form a planar portion, thereby giving the front end portion a generally D-shaped cross-section. A recess is formed on the curved surface portion of the front end.

2. The rotating shaft as described in claim 1, characterized in that, The recess is formed into a uniform groove along the circumference of the rotation axis.

3. The rotating shaft as described in claim 1, characterized in that, Multiple recesses are formed in the circumferential direction of the rotating shaft.

4. The rotating shaft as described in claim 1, characterized in that, The axial cross-section of the recess is approximately rectangular.

5. The rotating shaft as described in claim 1, characterized in that, The cross-section of the recess along the axial direction is arc-shaped.

6. The rotating shaft as claimed in claim 1, characterized in that, The wall on the front end side of the rotating shaft of the recess slopes from the front end side to the root side as it moves away from the bottom of the recess, and the angle between the wall and the outer peripheral surface of the rotating shaft is an acute angle.

7. The rotating shaft as described in claim 6, characterized in that, The wall on the root side of the rotating shaft of the recess is formed approximately vertically from the bottom of the recess.

8. The rotating shaft as described in claim 6, characterized in that, The wall on the root side of the rotating shaft of the recess rises approximately vertically from the bottom of the recess and bends into a convex shape towards the root side of the rotating shaft.

9. The rotating shaft as described in claim 6, characterized in that, The wall on the root side of the rotating shaft of the recess is formed by bending into a concave shape in a manner that gradually rises from the state along the bottom of the recess.

10. The rotating shaft as claimed in claim 6, characterized in that, The wall on the root side of the rotating shaft of the recess is formed in an arc shape.

11. A mounting structure for mounting components onto the rotating shaft of claim 1, characterized in that, An insertion hole, having approximately the same shape as the root and the front end, is formed on the mounting component, which can be fitted into the root and the front end. A D-spring, capable of engaging with the front end, is pressed into the portion of the insertion hole corresponding to the front end. The D spring has an inwardly deformed contraction portion. When the rotating shaft is inserted into the insertion hole and the mounting component is mounted on the rotating shaft, the contraction portion elastically engages with the recess.

12. The mounting structure as described in claim 11, characterized in that, The cross-section of the recess along the axial direction is approximately rectangular.

13. The mounting structure as described in claim 11, characterized in that, The cross-section of the recess along the axial direction is arc-shaped.

14. The mounting structure as described in claim 11, characterized in that, The wall on the front end side of the rotating shaft of the recess slopes from the front end side to the root side as it moves away from the bottom of the recess, and the angle between the wall and the outer peripheral surface of the rotating shaft is an acute angle.

15. The mounting structure as described in claim 14, characterized in that, The wall on the root side of the rotating shaft of the recess is formed approximately vertically from the bottom of the recess.

16. The mounting structure as described in claim 14, characterized in that, The wall on the root side of the rotating shaft of the recess rises approximately vertically from the bottom of the recess and bends into a convex shape towards the root side of the rotating shaft.

17. The mounting structure as described in claim 14, characterized in that, The wall on the root side of the rotating shaft of the recess is formed by bending into a concave shape in a manner that gradually rises from the state along the bottom of the recess.

18. The mounting structure as described in claim 14, characterized in that, The wall on the root side of the rotating shaft of the recess is formed in an arc shape.

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